Laminated object manufacturing process, materials and applications
Laminated object manufacturing, usually shortened to LOM, is a sheet lamination additive manufacturing process. It does not extrude filament, cure resin or fuse powder. Instead, it bonds sheets of material into a stack and cuts each layer to the required cross-section. The process is most closely associated with paper, plastic film and metal foil, although actual capability depends on the machine, adhesive system and cutting method.
For manufacturers, LOM is not a replacement for every 3D printing or machining process. Its value is in relatively fast, low-cost production of visual models, form studies, casting patterns and selected tooling aids where sheet-based construction is acceptable. The tradeoff is also clear: LOM can be efficient for bulky external shapes, but it is less suitable for fine internal channels, high-strength functional parts or components that need very smooth as-built surfaces.
This guide is part of our manufacturing processes coverage and focuses on practical process selection rather than vendor claims.
Where laminated object manufacturing fits in additive manufacturing
In standard additive manufacturing terminology, laminated object manufacturing belongs to the sheet lamination family. ISO/ASTM terminology describes sheet lamination as a process in which sheets of material are bonded to form a part. LOM is one of the best-known examples of that family, while ultrasonic additive manufacturing is another sheet lamination approach used mainly with metal foils.
This classification matters because many search results loosely describe any layer-based process as 3D printing. In engineering decisions, the feedstock form changes the economics and the design rules. Powder bed fusion starts with powder. Material extrusion starts with filament, pellets or paste. Vat photopolymerization starts with liquid resin. LOM starts with sheet stock. That difference affects cost, waste, surface finish, anisotropy, nesting, removal of excess material and the types of geometries that are realistic.
LOM is also historically important. It was among the early commercial additive manufacturing technologies of the late 1980s and early 1990s. Public summaries from the U.S. National Science Foundation and additive manufacturing histories associate the process with Michael Feygin and Helisys. The original appeal was straightforward: paper and other sheet materials were familiar, the build did not require loose powders or vats of resin, and large visual models could be produced from stacked layers.
How the LOM process works
A typical laminated object manufacturing workflow combines additive and subtractive steps. The machine adds a sheet, bonds it to the stack, and then cuts the layer profile. The exact sequence varies by machine design, but the engineering logic is consistent.
| Step | What happens | Why it matters |
|---|---|---|
| 1. Digital slicing | A CAD model is divided into layer cross-sections. | Layer thickness is linked to sheet thickness, so slicing strategy influences accuracy and surface stepping. |
| 2. Sheet feeding | A new sheet of paper, polymer film, composite tape or foil is positioned over the build area. | Feed stability affects registration between layers. |
| 3. Lamination | Heat, pressure, adhesive or another bonding mechanism joins the new sheet to the previous layer. | Bond quality controls part integrity, warping risk and delamination resistance. |
| 4. Cutting | A laser, knife or other cutter traces the layer outline and may score excess material. | Cut width, edge quality and thermal effects influence dimensional accuracy. |
| 5. Platform movement | The build platform lowers by one layer, and the next sheet is added. | Consistent Z movement helps maintain layer registration. |
| 6. Decubing and finishing | Excess material is removed, and the part may be sanded, sealed, painted or machined. | Post-processing can be simple for open shapes but difficult around fragile or complex features. |
Many LOM systems cut a cross-hatch or grid into the surrounding waste. This makes the unused block easier to break away after the build. The surrounding material also acts as a natural support during fabrication, which is one reason LOM can create some overhangs without separate support structures. The same feature becomes a limitation when geometry traps waste inside narrow cavities or undercuts.
Materials and part characteristics
The most familiar LOM material is adhesive-coated paper. When bonded into a dense stack, paper-based LOM parts can have wood-like handling characteristics and can often be sanded, sealed or painted for presentation models. This is why the process has long been linked with appearance prototypes, architectural models and concept validation.
Plastic films can extend the process toward more durable models, depending on the polymer and bonding method. Metal foil versions exist in the wider sheet lamination family, but engineers should not assume that a paper LOM machine and a metal sheet lamination machine have comparable performance. Metal sheet lamination usually requires a different bonding mechanism, machine structure and post-processing plan.
Composite and ceramic tapes have also been explored in technical literature, especially for specialized prototypes and research applications. For production decisions, however, material availability should be verified with the actual equipment supplier or service provider. The term LOM describes a process principle, not a universal material capability.
Part performance is strongly directional. Because the object is made from bonded sheets, properties in the plane of the sheet can differ from properties through the build direction. Adhesive quality, temperature, pressure, sheet surface condition and layer orientation all influence strength. For non-load-bearing models, this may be acceptable. For functional mechanical components, anisotropy and bond-line behavior need careful evaluation.
Advantages and limitations of LOM
The practical strengths of laminated object manufacturing come from its sheet-based feedstock. Sheets are often easier to handle than powders, and some sheet materials are inexpensive compared with specialized resins or metal powders. Large, bulky models can sometimes be produced efficiently because each layer covers a full sheet area before cutting.
| Potential advantage | Practical meaning |
|---|---|
| Readily available sheet materials | Paper and some films can reduce material cost for visual and form-check models. |
| No loose powder handling | The process avoids powder recovery, powder contamination and some powder safety concerns. |
| Natural support from surrounding stock | The uncut or partially cut stack can support overhangs during the build. |
| Useful for larger visual models | Bulky shapes that do not need fine internal detail can be well suited to LOM. |
| Finishable surfaces | Paper-based parts can often be sanded, sealed and painted for presentation use. |
The limitations are just as important. LOM requires excess material to be removed after building, so it is not purely material-efficient. The waste may be acceptable for low-cost paper, but it becomes more significant when using expensive films, foils or composite sheets. Internal features are another major constraint. Channels, enclosed cavities and fine undercuts can trap unwanted material and make decubing difficult or impossible.
Surface finish depends on layer thickness and cutting quality. Like other layer-based methods, LOM can show stair-stepping on sloped surfaces. Laser-cut edges may show heat effects depending on the material. Knife-cut systems avoid some thermal issues, but they introduce tool wear and cutting force considerations. Tolerances should therefore be confirmed for the actual material-machine combination rather than assumed from a general description of the process. See also: buying guides.
Common applications in manufacturing
LOM is most convincing when the part requirement matches the natural strengths of sheet lamination. It is usually a poor choice if the buyer expects dense, isotropic, end-use mechanical performance without additional validation. It can be a strong choice when the goal is to communicate shape, evaluate scale or create a low-cost physical reference.
- Visual prototypes: Product teams can use LOM models to review size, ergonomics, styling and assembly envelope before committing to tooling.
- Architectural and topographic models: The stacked-layer appearance can suit terrain, building massing and display models, especially when finishing is planned.
- Foundry patterns and form tools: LOM has been discussed in foundry contexts because large patterns can be built from sheet material and finished after printing.
- Packaging and industrial design mockups: The process can support early design reviews where surface appearance matters more than final material properties.
- Education and process demonstration: Because the laminate-and-cut principle is visible and intuitive, LOM is useful for explaining additive manufacturing categories.
For production tooling, fixtures or jigs, LOM should be evaluated case by case. A laminated part may be adequate for checking geometry or supporting a light-duty operation, but repeated load, humidity, temperature and wear can expose weaknesses at the bond lines. Sealing and secondary machining may improve usability, but they also add process time.
LOM compared with other manufacturing processes
Choosing LOM is easier when it is compared with realistic alternatives. The table below summarizes typical decision factors, not absolute rankings. Actual results depend on machine size, material, software, operator skill and finishing requirements.
| Process | Best fit | Typical limitation | Typical advantage |
|---|---|---|---|
| LOM | Large visual models, form studies, selected patterns | Difficult internal cavities and sheet waste | Low-cost sheet feedstock and natural support |
| FDM or FFF | Functional plastic prototypes, fixtures, quick iteration | Visible bead lines and support removal | Broader desktop availability and engineering thermoplastics |
| SLA or resin printing | Fine detail, smooth visual parts, small accurate models | Resin handling and post-curing | Higher detail and smoother surfaces for many small parts |
| SLS or powder bed fusion | Complex polymer parts and internal features | Powder handling and equipment cost | Better freedom for complex geometry |
| CNC machining | Accurate parts from production-grade stock | Material removal and setup for complex shapes | Superior material integrity for many functional components |
The key comparison is geometry. If a design contains internal lattices, enclosed channels or complex undercuts, a powder bed or resin process may be more appropriate. If the part is a large external form that will be painted or used as a pattern, LOM may be competitive. If the part must carry load in a production environment, CNC machining or a validated functional additive process is often safer.
Design and sourcing checklist
Before selecting laminated object manufacturing, engineers should define the purpose of the part. A model for a boardroom review has different requirements from a fixture used on a shop floor. The following checklist helps avoid mismatched expectations.
- Confirm the material: Ask whether the build uses paper, polymer film, composite tape or foil, and request the relevant finishing options.
- Check layer thickness: Sheet thickness affects Z resolution, stair-stepping and the amount of finishing needed.
- Review internal geometry: Avoid closed voids and narrow trapped areas unless the provider confirms a removal method.
- Discuss adhesive and environment: Temperature, humidity and chemical exposure can matter for laminated paper or adhesive-bonded parts.
- Define tolerances early: Do not apply machined-part tolerances unless secondary machining is included.
- Plan finishing: Sanding, sealing, painting or coating may be necessary for appearance or durability.
- Consider waste removal: Large fragile parts may require careful decubing and handling after the build.
- Compare alternatives: Quote LOM against FDM, SLA, SLS or CNC based on the same CAD model and acceptance criteria.
The best use of LOM is selective. It is not outdated simply because newer additive processes are more visible, but it is not a universal solution either. For the right geometry and purpose, laminated object manufacturing remains a useful example of how additive manufacturing can be built around sheet stock rather than powders, liquids or extruded material.
Frequently asked questions
Is laminated object manufacturing the same as sheet lamination?
Not exactly. Sheet lamination is the broader additive manufacturing category. Laminated object manufacturing is a specific and well-known process within that category. Other processes, such as ultrasonic additive manufacturing, also fall under sheet lamination but use different bonding principles and materials.
What materials are used in laminated object manufacturing?
Commonly discussed LOM materials include adhesive-coated paper, plastic films and metal foils. Paper-based LOM is the most familiar form for visual models. Metal and composite sheet lamination require process-specific equipment and should be evaluated separately from basic paper LOM.
Does LOM need support structures?
LOM usually does not need separate support structures in the same way as FDM or SLA. The surrounding sheet stack supports the part during the build. However, that material must be removed afterward, and removal can be difficult if the design contains trapped cavities or delicate internal features.
Is laminated object manufacturing suitable for functional end-use parts?
It can be suitable for some low-load or specialized uses, but it is more often chosen for visual prototypes, patterns and models. Functional use depends on material, bond strength, environment, geometry and finishing. For critical mechanical parts, the process should be validated with testing rather than assumed suitable.
When should a manufacturer consider LOM instead of FDM or SLA?
Consider LOM when the part is relatively large, mostly defined by external shape, and intended for visual review, patternmaking or form validation. FDM may be better for practical plastic fixtures, while SLA is often better for small, smooth, detailed parts.
